The present invention is directed to improvements in packaging structure and apparatus useful in its assembly. While of broader applicability, the invention is particularly useful in the assembly of top-opening cartons of the so-called flip-top type.
In the assembly of packaging structure, such as top-opening cartons, it has been found difficult to form side or end flaps thereof economically while providing a carton that is easily opened along a line of weakness. In top-opening cartons of the flip-top type, a closure or cover is provided in the form of a panel hinged to the carton body along a fold line. The remaining three sides of the closure have flaps that overlap adjacent carton wall panels, and at least the opposed flaps are sealed thereto by flap extensions provided with lines of weakness. Contents of the carton are accessible by lifting the closure about its hinged connection while tearing the flap extensions along corresponding lines of weakness. The lines of weakness, of course, must be readily tearable in order that the carton not be so damaged as to prevent its reclosure.
It is a general objective of this invention to provide improved carton structure of the aforementioned type, and apparatus facilitating its assembly.